UIActivityViewController With Alternate Filename? - ios

Question

I am sharing an audio recording via the UIActivityViewController. When the audio file shares via email or iMessage, it shows the underlying name of the audio file without any apparent way of changing it.
NSArray *activityItems = [NSArray arrayWithObjects:self.audioPlayer.url, nil];
UIActivityViewController *avc = [[UIActivityViewController alloc]
initWithActivityItems:activityItems
applicationActivities:nil];
[self presentViewController:avc
animated:YES completion:nil];
If I don't use the UIActivityViewController and just use MFMessageComposeViewController directly, than I can use
[composer addAttachmentURL:self.audioPlayer.url withAlternateFilename:#"Piano Song.m4a"];
Is it possible to have an alternate file name with the UIActivityViewController?

Answer 1

You can create a hard link to the file (so that you don't have to copy the actual file) with any name you want in the temporary directory and pass it to the UIActivityViewController instead of the file.
- (NSURL *)createLinkToFileAtURL:(NSURL *)fileURL withName:(NSString *)fileName {
NSFileManager *fileManager = [NSFileManager defaultManager];
// create a path in the temp directory with the fileName
NSURL *tempDirectoryURL = [[NSFileManager defaultManager] temporaryDirectory];
NSURL *linkURL = [tempDirectoryURL URLByAppendingPathComponent:fileName];
// if the link already exists, delete it
if ([fileManager fileExistsAtPath:linkURL.path]) {
NSError *error;
[fileManager removeItemAtURL:linkURL error:&error];
if (error) {
// handle the error
}
}
// create a link to the file
NSError *error;
BOOL flag = [fileManager linkItemAtURL:fileURL toURL:linkURL error:&error];
if (!flag || error) {
// handle the error
}
return linkURL;
}
Use it like this:
NSURL *fileURL = ...;
NSString *desiredName = ...;
NSURL *linkURL = [self createLinkToFileAtURL:fileURL withName:desiredName];
UIActivityViewController *viewController = [[UIActivityViewController alloc] initWithActivityItems:#[linkURL] applicationActivities:nil];
[self presentViewController:viewController animated:YES completion:nil];
Hope this helps! Good luck!

Answer 2

Very nice, timaktimak. Thank you.
Here is the same in Swift:
private func createLinkToFile(atURL fileURL: URL, withName fileName: String) -> URL? {
let fileManager = FileManager.default // the default file maneger
let tempDirectoryURL = fileManager.temporaryDirectory // get the temp directory
let linkURL = tempDirectoryURL.appendingPathComponent(fileName) // and append the new file name
do { // try the operations
if fileManager.fileExists(atPath: linkURL.path) { // there is already a hard link with that name
try fileManager.removeItem(at: linkURL) // get rid of it
}
try fileManager.linkItem(at: fileURL, to: linkURL) // create the hard link
return linkURL // and return it
} catch let error as NSError { // something wrong
print("\(error)") // debug print out
return nil // and signal to caller
}
}

Answer 3

No, not possible. Could you not just rename the file before sharing it?